A substrate processing apparatus is used in the process of manufacturing semiconductors, liquid crystal panels, and the like to supply a treatment solution (e.g., chemical solution such as resist stripping solution and etchant, etc., a rinsing liquid such as pure water, etc.) to a surface of a substrate, such as a wafer or a liquid crystal substrate, to thereby treat the surface.
Among such substrate processing apparatuses are those that perform spinning process in which they rotate a substrate horizontally and supply a treatment solution to substantially the center of a surface of the substrate from a nozzle so that the treatment solution is spread over the surface by centrifugal force of the rotation. Further, there have also been developed apparatuses that supply a chemical solution by spraying it from the nozzle to the back surface of a rotating substrate in addition to the surface thereof to treat both the surfaces of the substrate.
After the above-described process has been performed on the substrate, both the surfaces of the substrate are subjected to cleaning process and cleaned with a rinsing liquid such as pure water, etc. Thereafter, drying process is performed to remove the rinsing liquid remaining on the substrate by rotating the substrate.
When the cleaning process and the drying process are performed on the back surface of the substrate, a rinsing liquid or a gas used for the drying process is discharged from a nozzle provided to the nozzle head. That is, the nozzle is arranged at a position facing the back surface which is the surface to be processed of the substrate. In addition, the nozzle head has a recess having a cross-sectional shape of an inverted cone with its opening toward the back surface.